Lös minst 2 av följande kattisuppgifter:
https://open.kattis.com/problems/fenwick
https://open.kattis.com/problems/unionfind
https://open.kattis.com/problems/guessthedatastructure
https://po.kattis.com/problems/kotid (segmentträd)
https://open.kattis.com/problems/aladin (lata segmentträd, https://github.com/kth-competitive-programming/kactl/blob/master/content/number-theory/ModSum.h)